carnetix and laptop

I recently aquired a compaq e500 laptop, and have decided to use it in the car. After searching, I am pretty sure how to power it in car with the carnetix p1900, but just want to confirm my ideas here.

In order for it to work, I just need to get a tip that fits into the laptop power supply splice that into the wires off the carnetix, and then select the correct voltage for the laptop, correct? Or am I way off base here?

You also need to make sure the laptop power connector is just a ground and voltage...a lot of new ones have a third (or more) pins that tell the laptop if you're using a original power brick and won't charge if you aren't.

Actually, if you are connecting the Carnetix PS to a laptop, you should be able to configure the Power Management properties of Windows to hibernate when external power is removed. (You would then be powering off the batteries of the laptop for the duration of the shutdown period.) Of course, the laptop wouldn't come back on automatically when power is restored, unless you have some sort of ACPI function in your BIOS to 'Turn on when power is restored'. This would be much easier than trying to connect an ACPI interface from the PSU to your laptop.

best way really is to use a car adaptor made for the laptop, like a lind or something... it's not that no car adaptor works, they do have one that will work with it, just has to be the right one...

I did a dell once... they use 3 pins... one ground, one 12v & one 19v, all from the same supply, but the laptop runs on the 19v alone no problem, just doesn't charge the battery.... I never tried giving it both voltages, but assumed it would work, but complicate it... I don't use batteries most times anyway, & if everything is wired correctly, you don't need the battery at all...

as far as setting up windows to hibernate as power is lost, that defeats the purpose of using a startup/shutdown controller in the first place... not only that, but for the power supply to even work, it does need to know weather the computer is on or of, otherwise it'll keep sending out a pulse to attempt to start it for the whole duration it's on!!.... it's not hard to do this interface at all... I did a thread once, it was an opus, but same thing really...

Does the P1900 have a startup/shutdown controller? I was thinking it was just a regulated PS with no fancy features. I have a dell inspiron 2200 and I plan on getting a motorized touchscreen and was going to power them from a P1900.

I was thinking it would work just as the original poster suggested. Now I'm kind of worried.

it does have a startup/shutdown controller. the biggest problem could be charging the battery I guess... do your research really, check for 3 connections or 2... the third is hard to notice but it's sometimes the inner part of the outer hole...